package course.d1221;
import java.util.LinkedHashMap;
import java.util.Map;
/*
   HashSet底层维护的是HashMap，HashSet集合的特点：无序不可重复

   LinkedHashMap extends HashMap;
   LinkedHashMap 集合维护了向集合中添加的顺序
   LinkedHashSet 底层维护的是LinkedHashMap
 */
public class p5 {
    public static void main(String[] args) {
        Map<String,String> map= new LinkedHashMap<>();
        map.put("101","jack");
        map.put("102","jack");
        map.put("103","jack");


        for (Map.Entry<String, String> entry : map.entrySet()) {
            System.out.println(entry);
        }
    }
}
